JP5890966B2 - Coil device - Google Patents

Description

  The present invention relates to a coil device including a heat dissipation case.

  In a large-capacity coil device (for example, a reactor) used in a drive system of a hybrid vehicle or an electric vehicle, a main body including a core and a coil is housed and fixed in a heat dissipation case. When fixing the main body, a filler such as resin is filled in the gap between the main body and the heat radiating case in order to improve the vibration characteristics of the coil device.

  However, since the filler has a low heat transfer rate, it prevents the heat generated by the core iron loss and copper loss from being efficiently released to the outside. In order to suppress the deterioration of the heat dissipation performance while maintaining good vibration characteristics of the coil device, the gap between the main body and the heat dissipation case when the main body is housed in the heat dissipation case is set narrow so that the bottleneck of the heat dissipation performance It is desirable to make the thickness of a certain filler layer as thin as possible. For that purpose, the positioning mechanism of the main body in the heat radiating case is important. For example, in the coil device described in Patent Document 1, an adhesive is applied to the outer peripheral surface of the U-shaped core or the inner wall surface of the recessed groove portion of the case corresponding to the U-shaped core, and then the U-core is fitted into the recessed groove portion. It is configured to position.

JP 2006-351675 A

  However, an unintended minute gap is generated between the outer peripheral surface of the U-shaped core and the inner wall surface of the groove portion depending on the manufacturing error of the component. If the adhesive does not wrap around this gap, an air layer with poor heat dissipation characteristics will result. Further, the more uneven the contact surface between the U-shaped core outer peripheral surface and the inner groove wall surface, the greater the noise when the outer U-core outer surface and the inner groove surface collide due to vibration. The adhesive may be peeled off due to vibration, thermal shock, or the like, and the thermal / vibration characteristics may deteriorate over time.

  A coil device according to an embodiment of the present invention that solves the above problems includes a main body and a main body housing case as described below. The main body is formed on a core covered with an insulating member, a coil that winds the outer periphery of the central portion of the core from above the insulating member, and an insulating member that covers both ends of the core around which the coil is not wound. And a convex portion having a predetermined positioning surface. The main body housing case has a contact surface at a position corresponding to the positioning surface on the inner wall surface. When the main body is accommodated in the main body accommodating case, the positioning surface is applied to the contact surface, and the main body is arranged at a predetermined position in the main body accommodating case.

  According to the coil device of the present invention, when the main body is positioned by the convex portion on the insulating member, the distance (gap) from the main body housing case can be easily managed in design. Since the gap between the main body and the main body housing case can be designed with high accuracy, an inflow path for the filler is ensured, and partial deterioration of the heat radiation characteristics due to filling unevenness (for example, an air layer) can be avoided. In addition, since the contact area between the main body and the main body housing case can be made absolutely small, noise when the main body and the main body housing case collide with each other due to vibration can be greatly suppressed, and filling with vibration, thermal shock, etc. The peeling of the agent is also effectively suppressed.

  In the orthogonal coordinate system defined by the first axis, the second axis, and the third axis, the coil is wound in a plane substantially parallel to the plane defined by the second axis and the third axis. It is good also as a structure which continues along one axis | shaft. In this case, the convex portion protrudes at least in the second axial direction, and the positioning surface abuts against the contact surface in the second axial direction.

  The coil device according to the present invention has, for example, a configuration in which the main body is accommodated close to the main body housing case along the third axis direction, and a part of the convex portion facing the contact surface is In order to improve the workability at the time of assembling the device, it may be a tapered surface that guides the movement of the positioning surface to the contact surface along the third axis direction.

  The core is, for example, a pair of substantially U-shaped portions at both ends, and a center portion is a pair of straight portions connecting the pair of substantially U-shaped portions, and a coil is wound around each of the pair of straight portions. Ring core. In this case, the convex part is formed on the insulating member which covers each curved surface of a pair of substantially U-shaped part.

  The width of the convex portion (in the third axial direction) may be set narrower than the width of the curved surface of the substantially U-shaped portion (in the third axial direction) in order to secure the inflow path of the filler.

  The main body may be fixed simultaneously with positioning in the main body housing case by fitting the positioning surface and the contact surface.

  The coil device according to the present invention may be configured to include a fixture that fixes the main body positioned in the main body housing case.

  The insulating member may be integrally formed with the core by insert molding. According to this configuration, the number of parts can be reduced and the work of attaching the insulating member to the core becomes unnecessary.

  A coil device according to another aspect of the present invention that solves the above problems includes a main body, a main body housing case, and a fixture as described below. The main body includes a core covered with an insulating member, a coil that winds the outer periphery of the central portion of the core from above the insulating member, and both ends of the core that is positioned around the central axis of the core and on which the coil is not wound. And at least a pair of convex portions having a predetermined positioning surface formed on an insulating member covering the portion. The main body housing case has a contact surface at a position corresponding to the positioning surface on the inner wall surface. The fixing tool fixes the main body to the main body housing case. When the main body is accommodated in the main body accommodating case, each positioning surface is applied to the corresponding abutting surface, and the movement of the main body in the main body accommodating case in one direction perpendicular to the central axis of the core is restricted. The The fixing device restricts the movement of the main body portion in the remaining direction, which cannot be restricted by the contact between the positioning surface and the contact surface.

  Each of the both end portions has a pair of side surface portions located, for example, with the central axis of the core interposed therebetween. In this case, at least one convex portion is formed on each side surface portion of each end portion.

  The fixing tool may be a biasing member that biases the main body portion in the remaining direction that cannot be regulated by applying the positioning surface and the abutting surface within the main body housing case.

  ADVANTAGE OF THE INVENTION According to this invention, the coil apparatus suitable for positioning a main-body part in a main-body-part accommodation case is provided.

It is a perspective view of the reactor which concerns on embodiment of this invention. It is a disassembled perspective view of the reactor which concerns on embodiment of this invention. It is a top view of the reactor which concerns on embodiment of this invention. It is AA sectional drawing in FIG. It is BB sectional drawing in FIG. It is a top view of the heat radiating case single-piece | unit which concerns on embodiment of this invention. It is a top view of the reactor main body single-piece | unit which concerns on embodiment of this invention. It is a side view of the reactor main body single-piece | unit which concerns on embodiment of this invention.

  Hereinafter, the reactor 1 which concerns on embodiment of this invention is demonstrated, referring drawings. 1 to 3 are a perspective view, an exploded perspective view, and a plan view of the reactor 1, respectively. 4 is a cross-sectional view taken along line AA in FIG. 3, and FIG. 5 is a cross-sectional view taken along line BB in FIG. In the following description, the direction from the lower right side to the upper left side in FIG. 1 is defined as the depth direction (X axis direction), and the direction orthogonal to the X axis direction and from the lower left side to the upper right side is defined as the width direction (Y The direction perpendicular to the two directions of the X axis and the Y axis and from the lower side to the upper side is defined as the height direction (Z axis direction). In addition, when using the reactor 1, you may arrange | position the reactor 1 toward which direction.

  As shown in FIG. 1 or FIG. 2, the reactor 1 includes a coil 10, a core module 20, fixtures 30 </ b> A and 30 </ b> B, a heat radiating case 50, and a terminal block 60. The reactor body 15 is configured by the coil 10 and the core module 20.

  The core module 20 includes two U-shaped core units 20A and 20B formed in a substantially U shape. Each of the U-shaped core units 20A and 20B has a configuration in which core blocks 21A and 21B made of a magnetic material are covered with an insulating resin by injection molding (insert molding). The resin covers only the side surface through which the magnetic flux does not pass, and does not cover the U-shaped tip surface (the end surface of the straight portion and the connection surface with the other U-shaped core unit) through which the magnetic flux passes. A heat resistant resin such as polyphenylene sulfide (PPS) is used for the coating resin of the U-shaped core units 20A and 20B. A dust core is used for each of the core blocks 21A and 21B. The dust core may be replaced with another material such as an electromagnetic steel plate or ferrite. Note that the coating resin is an alternative to an insulating bobbin that has been conventionally used to ensure electrical insulation between the core and the coil, and corresponds to a structure in which the insulating bobbin and the core are integrally formed.

  The core module 20 is formed by abutting the U-shaped end faces of the U-shaped core units 20A and 20B through a gap member (not visible in the drawing since the coil 10 is wound) and bonding them with an adhesive. An O-shaped ring core is formed. The gap member is, for example, a plate material made of a non-magnetic material (various ceramics such as alumina or resin).

  The U-shaped core unit 20A includes a pair of substantially rectangular parallelepiped portions extending in the X-axis direction and arranged in parallel to each other (not visible in the drawing because the coil 10 is wound), and ends of the pair of straight portions. Are connected by a connecting portion 24A. A flange portion 25A formed of a coating resin is provided on a side surface of the U-shaped core unit 20A. The flange portion 25A is a plate-like portion that extends in the YZ plane, and is disposed on a plane that forms a boundary between the connecting portion 24A and the linear portion. Similarly to the U-shaped core unit 20A, the U-shaped core unit 20B has a configuration in which a pair of linear portions are coupled by a coupling portion 24B, and a flange portion 25B is provided on a side surface. In addition, although the ring core of this embodiment is a 2 piece structure of U-shaped core units 20A and 20B, in another embodiment, you may be comprised with components of 3 pieces or more. For example, the connecting portions 24A and 24B and the straight portion may be separate parts, and the connecting portions 24A and 24B and a four-piece configuration including a pair of straight portions may be used.

  The coil 10 has a configuration in which linear coil portions 12 and 14 having the same structure are arranged in parallel and one ends thereof are connected by a connecting wire 16. The linear coil portions 12 and 14 are formed by bending a flat enameled wire in a right angle direction at four locations per turn and winding it in a substantially square shape.

  After the gap member is placed on each of the pair of tip surfaces (end surfaces of the straight portions) of the U-shaped core unit 20A (or 20B) and the straight portions are inserted into the hollow portions of the two straight coil portions 12 and 14 of the coil 10, respectively. When the straight portions of the U-shaped core unit 20B (or 20A) are inserted into the hollow portions from the opposite side of the coil 10 and the tip surfaces of the U-shaped core units 20A and 20B are brought into contact with each other via a gap member, the reactor is bonded. The main body 15 is completed. The coil 10 is sandwiched between the flange portion 25A of the U-shaped core unit 20A and the flange portion 25B of the U-shaped core unit 20B, and the position in the X-axis direction with respect to the core module 20 is determined.

  The reactor body 15 assembled as described above is accommodated in the heat dissipation case 50 and fixed to the heat dissipation case 50 by the fixtures 30A and 30B. Specifically, the heat radiating case 50 is a member having a substantially rectangular parallelepiped housing space formed of a metal (for example, an aluminum alloy) having high thermal conductivity and light weight. The fixtures 30A and 30B are both members formed by pressing a stainless steel plate. When the fixtures 30A and 30B are respectively fixed to the heat dissipation case 50 with bolts, the reactor main body 15 (directly the core module 20) has the lower surface and the inner side surface of the heat dissipation case 50 (FIG. 2) due to the elastic force of the fixtures 30A and 30B. Is firmly pressed to the heat radiating case 50.

  After the reactor main body 15 is fixed to the heat radiating case 50, a filling material (not shown for convenience) which is a relatively soft and highly heat conductive resin is filled in the gap in the heat radiating case 50. Thereby, the vibration propagation from the reactor main body 15 to the heat radiating case 50 is reduced while the necessary heat dissipation performance of the reactor main body 15 is ensured.

  A terminal block 60 is attached to one end of the edge of the heat radiating case 50 with bolts. The terminal block 60 includes bus bars 62a and 62b. The bus bars 62a and 62b are welded to the lead portions 121 and 141 of the coil 10, respectively.

  Most of the heat generated in the core blocks 21A and 21B during operation is transmitted to the heat radiating case 50 through the filler filled in the gap between the reactor body 15 and the heat radiating case 50, and is radiated to the outside. The gap filled with the filler is the place where the heat transfer speed is the slowest in the heat dissipation path. Therefore, the thickness of the filler layer is one of the main factors that determine the heat dissipation performance of the reactor 1. In order to suppress the deterioration of the heat dissipation performance while maintaining the vibration characteristics of the reactor 1 satisfactorily, the gap between the reactor body 15 and the heat dissipation case 50 when the reactor body 15 is accommodated in the heat dissipation case 50 is set narrow, and the filler It is desirable to make the thickness of the layer as thin as possible. Therefore, the reactor body 15 is accurately positioned in the heat dissipation case 50. In addition, the set value of the gap (the thickness of the filler layer) between the reactor body 15 and the heat radiating case 50 is the dimensional accuracy, assembly accuracy, fluidity of the filler, vibration during operation, external It is determined after comprehensively considering parameters such as the amount of displacement of the core module 20 due to the impact received from.

  In addition to the method described in Patent Document 1, there are the following methods for positioning and fixing the reactor body. For example, a method of fixing the position of the reactor body by directly pressing a rib provided on the inner surface of the heat radiating case against the core surface before injecting the filler into the gap in the heat radiating case can be considered. However, since stress is concentrated on the core surface against which the rib is pressed, the core may be damaged. Another possible method is to fix the position of the reactor body in the heat dissipation case by extending the flange portion of the insulating bobbin and applying it to the heat dissipation case. However, since the flange portion has a thin resin plate shape, there are problems that it is difficult to mold with high accuracy and load resistance and impact resistance are low.

  Therefore, in the present embodiment, the reactor body 15 is positioned and fixed in the heat radiating case 50 as follows, so that the deterioration of the heat radiating performance is suppressed while maintaining the vibration characteristics of the reactor 1 satisfactorily.

  FIG. 6 is a top view of the heat radiating case 50 alone. 7 and 8 are a top view and a side view, respectively, of the reactor main body 15 alone. As shown in FIG. 3 or FIG. 6, contact surfaces 51 parallel to the XZ plane are formed at the four corners of the inner surface of the substantially rectangular parallelepiped housing space of the heat radiating case 50. Further, as shown in FIG. 7, positioning convex portions 26 (covering resin) are formed on the left and right curved surface portions of the side surface of the connecting portion 24A. A pair of positioning convex portions 26 are also formed in the connecting portion 24B at the same position as the connecting portion 24A. That is, a total of four positioning convex portions 26 are arranged on the curved surfaces of the connecting portions 24A and 24B located across the central axis AX of the reactor main body 15. Note that the central axis AX of the reactor body 15 is an axis in the X-axis direction included in the BB cross section of FIG. Each positioning projection 26 is formed with a positioning surface 26a parallel to the XZ plane. As shown in FIG. 8, the lower surface of the positioning convex portion 26 is a tapered surface 26b formed in a tapered shape.

  The inner surface of the heat radiating case 50 located at the upper part of each contact surface 51 is gently inclined or has a relief shape with respect to the positioning convex portion 26. When the reactor main body 15 is lowered toward the inner bottom surface of the heat radiating case 50, each of the four tapered surfaces 26b hits the inner side surface of the heat radiating case 50 to guide the housing of the reactor main body 15 roughly. When the reactor body 15 is pushed toward the inner bottom surface of the heat radiating case 50 in this state, the positioning surface 26a is applied to the abutting surface 51 at each corner of the inner surface, and the inner bottom surface side (Z-axis direction) is in contact with the surface. Is pushed into. By pushing the reactor main body 15 until the lower surfaces of the connecting portions 24A and 24B are brought into contact with the receiving surface 52 of the heat radiating case 50, the position of the reactor main body 15 in the heat radiating case 50 can be simply and accurately without using a fastening member or the like. Thus, the housing of the reactor main body 15 in the heat radiating case 50 is completed. Furthermore, when the fixing tools 30 </ b> A and 30 </ b> B are each fixed to the heat radiating case 50 with bolts and filled with a filler, the reactor body 15 is fixed in the heat radiating case 50.

  Note that the position dimensions of the positioning surface 26a and the contact surface 51 may be defined by a fit tolerance (intermediate fit or interference fit). In this case, when the positioning surface 26 a and the contact surface 51 come into contact with each other, the positioning convex portion 26 or the side wall surface of the heat radiating case 50 is elastically deformed, and an appropriate tightening force in the Y-axis direction is applied to the reactor body 15 through the positioning convex portion 26. Work. Depending on the setting of the tightening force, not only the Y-axis direction but also the movement of the reactor body 15 in the X-axis direction and the Z-axis direction can be firmly restricted. That is, the reactor body 15 can be fixed in the heat dissipation case 50 even when the receiving surface 52 and the fixtures 30A and 30B are not provided.

  Since the reactor main body 15 is accurately positioned by the positioning convex portion 26, the gap with the heat radiating case 50 can be set narrow. The clearance is ensured over substantially the entire circumference of the reactor main body 15 except for a part (a contact portion between the lower surface of the coupling portions 24A and 24B and the receiving surface 52 and a contact portion between the positioning surface 26a and the contact surface 51). Is done. Since the filler flows into a narrow gap over substantially the entire circumference of the reactor main body 15, it is possible to favorably suppress a decrease in heat dissipation performance while maintaining good vibration characteristics of the reactor 1.

  In the present embodiment, the distance (gap) between the reactor body 15 and the heat radiating case 50 can be defined by the height dimension (Y-axis direction) of the positioning convex portion 26, so that the gap can be easily managed in design. Since the gap between the reactor main body 15 and the heat radiating case 50 can be designed with high accuracy, an inflow path for the filler is ensured, and partial deterioration of the heat radiation characteristics due to filling unevenness (for example, an air layer) is avoided. Further, since the contact area between the reactor main body 15 and the heat radiating case 50 can be made absolutely small, noise when the reactor main body 15 and the heat radiating case 50 collide with each other due to vibration is greatly suppressed, and filling by vibration or thermal shock is performed. The peeling of the agent is also effectively suppressed. Moreover, since the positioning convex part 26 formed as a part of coating resin is applied to the contact surface 51, the direct external stress with respect to the core block 21A or 21B is avoided effectively. Therefore, the risk of damage to the core block 21A or 21B is greatly reduced.

  The flange portions 25A and 25B have a role of regulating the movement of the linear coil portions 12 and 14 in the X-axis direction. In order to fulfill this role, the flange portions 25A and 25B are required to have a height (Z-axis direction) and width (Y-axis direction) that are equal to or greater than the coil diameter. Therefore, the flange portions 25A and 25B must be thin plate shapes. Further, when positioning the flange portions 25A and 25B against the heat radiating case 50, the flange portion 25A divides the gap between the coil 10 and the connection portion 24A, and the flange portion 25B is connected to the coil 10 and the connection portion. Divide the gap around 24B. Therefore, the filler does not go around the entire circumference of the reactor body 15. On the other hand, the height and width of the positioning convex portion 26 are not particularly limited with respect to the lower limit. Therefore, the positioning convex portion 26 is narrower than the flange portions 25A and 25B (Z-axis direction) and has a predetermined reference surface (linear coil) in order to ensure load resistance / impact resistance and an inflow path for the filler. The height (Y-axis direction) from the plane including the winding axis of the portion 12 or 14 is kept low. The positioning convex portion 26 is narrower than the width (Z-axis direction) of the curved surface of the connecting portion 24A with respect to the width (Z-axis direction).

  The above is the description of the exemplary embodiments of the present invention. Embodiments of the present invention are not limited to those described above, and can be arbitrarily changed within the scope of the technical idea expressed by the description of the scope of claims.

  In the above-described embodiment, a total of four positioning surfaces 26a are arranged on each curved surface of the core module 20, but in another embodiment, five or more positioning surfaces 26a may be arranged.

  The above embodiment is an example in which the present invention is applied to a reactor, but the present invention may be applied to another type of coil device (for example, a transformer).

DESCRIPTION OF SYMBOLS 1 Reactor 10 Coil 20 Core module 26 Positioning convex part 26a Positioning surface 26b Tapered surface 30A, 30B Fixing tool 50 Radiating case 51 Contact surface

Claims (13)

A core covered with an insulating member;
A coil for winding the outer periphery of the central portion of the core from above the insulating member;
A main body having
A main body housing case having heat dissipation to house the main body,
With
The insulating member has a pair of positioning protrusions protruding from the portions covering both ends of the core;
The pair of positioning convex portions sandwich the core in a plane perpendicular to the first axis of the orthogonal coordinate system defined by the first axis, the second axis, and the third axis,
When the main body is accommodated in the main body accommodating case, the positioning protrusions are respectively applied to the inner wall surface of the main body accommodating case, and the main body is positioned at a predetermined position in the main body accommodating case. configured to be placed,
The coil apparatus characterized by the above-mentioned. The positioning projection has a positioning surface that comes into contact with the inner wall surface of the main body housing case;
The inner wall surface of the main body storage case has a pair of contact surfaces that come into contact with the positioning surface,
The coil device according to claim 1. The coil has the first axis substantially parallel to the winding shaft,
The positioning projection protrudes at least in the second axial direction;
The coil device according to claim 2, wherein the positioning surface is in contact with the contact surface in the second axial direction. The main body is configured to be accommodated close to the main body housing case along the third axis direction,
The partial surface of the positioning convex portion facing the contact surface is a tapered surface that guides the movement of the positioning surface to the corresponding surface along the third axis direction. Item 4. The coil device according to Item 3. The both ends of the core are a pair of substantially U-shaped portions, and the central portion is a pair of straight portions connecting the pair of substantially U-shaped portions, and each of the pair of straight portions includes the A ring core around which a coil is wound,
The said positioning convex part is formed on the said insulation member which covers each curved surface of a pair of said substantially U-shaped part, The Claim 1 characterized by the above-mentioned Coil device.   6. The coil device according to claim 5, wherein a width of the positioning convex portion is narrower than a width of the curved surface in the third axial direction.   The coil device according to any one of claims 2 to 6, wherein the main body is fixed in the main body housing case by fitting the positioning surface and the contact surface. .   The coil device according to any one of claims 2 to 7, further comprising a fixture that fixes the main body to the main body housing case.   The coil device according to any one of claims 2 to 8, wherein the insulating member is formed integrally with the core by insert molding. A core covered with an insulating member;
A coil for winding the outer periphery of the central portion of the core from above the insulating member;
At least a pair of positioning projections having a predetermined positioning surface, which is formed on the insulating member covering the both ends of the core where the coil is not wound, which is located across the central axis of the core;
A main body having
On the inner wall surface, the main body housing case having heat dissipation having a contact surface at a position corresponding to each positioning surface,
A fixture for fixing the main body to the main body housing case;
With
The pair of positioning convex portions sandwich the core in a plane perpendicular to the central axis,
When the main body portion is accommodated in the main body housing case perpendicular, is abutted against the abutment surfaces each said locating surface corresponds, at least the central axis of the body portion of the main body portion accommodating the casing one direction of movement that is configured so that is regulated,
The coil device is characterized in that the fixing device restricts the movement in the remaining direction of the main body portion that cannot be restricted by applying the positioning surface and the contact surface. Each of the both end portions has a pair of side surface portions located across the central axis,
11. The coil device according to claim 10, wherein at least one positioning convex portion is formed on each side surface portion of each of the both end portions.   The coil device according to claim 10 or 11, wherein the fixing member is a biasing member that biases the main body portion in the remaining direction within the main body portion housing case. The coil device according to any one of claims 1 to 12, wherein a filler is filled in a gap between the main body housing case and the main body.

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